Wednesday, August 6, 2008

Plant Photosynthesis Leads to Cheap Storage of Solar Energy

The amount of sunlight that strikes the Earth in one hour supplies the entire planets energy needs for one year. Current technology to store excess carbon-free electricity during the day, to be used during heavily overcast days and at night, is too cost prohibitive and grossly inefficient to realize its full potential as a cheap, reliable, renewable energy source.

Researchers at Massachusetts Institute of Technology (MIT) have devised a simple method that will overcome both the high cost and the inefficiency of current solar electrical storage. They can now mimic plant photosynthesis to split water molecules into hydrogen and oxygen and then recombine them inside a fuel cell, creating carbon-free electricity to power your house or your electric car, day or night.
(Photo credit: MIT/NSF; the new, efficient oxygen catalyst in action in Dan Nocera's laboratory at MIT.)

Daniel Nocera Matthew Kanan were inspired by plant photosynthesis to use a catalyst consisting of cobalt metal, phosphate and an electrode to produce oxygen gas from water, another catalyst produces hydrogen gas. Electricity, whether produced from a photovoltaic cell, a wind turbine or any other source, runs through the electrode resulting in oxygen gas. Another catalyst, using platinum, can produce hydrogen from water.

The new catalyst works at room temperature, in neutral pH water, and it's easy to set up, Nocera said. "That's why I know this is going to work. It's so easy to implement," he said.

Electrolyzers currently in use by industry are not suited to artificial photosynthesis because they are very expensive and require a highly basic (non-benign) environment that has little to do with the conditions under which photosynthesis operates.

This new discovery, along with solar panels as thin as paint for homes and cars, and with nano flakes revolutionizing the transformation of solar energy to electricity, will greatly reduce our dependence on fossil fuels and address global climate change. The biggest obstacle remaining is the government in legislating the switch-over from electricity-by-wire from a central source and big oil, who will not want to see the loss of income to their already abundantly over-flowing coffers. For individual home owners, the future is indeed looking brighter.


Further reading:
Home Windows Could Cut Carbon Emissions in Half

Cheap New Solar Panels

Nanosolar Powersheet That Could Change the World

Cheap, Green Solar Panels

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